APA (7th ed.) Citation

Roberts, E. A., & Lawrence, J. R. (1935). American ferns: How to know, grow and use them. Macmillan.

Chicago Style (17th ed.) Citation

Roberts, Edith Adelaide, and Julia Ruth Lawrence. American Ferns: How to Know, Grow and Use Them. New York: Macmillan, 1935.

MLA (9th ed.) Citation

Roberts, Edith Adelaide, and Julia Ruth Lawrence. American Ferns: How to Know, Grow and Use Them. Macmillan, 1935.